What should be paid attention to when using a photovoltaic welding strip rolling mill

       The core function of the photovoltaic welding strip rolling mill is to roll the copper strip substrate into ultra-thin and high-precision welding strips that meet the welding requirements of photovoltaic modules. The use process should revolve around four core aspects: precision control, equipment safety, product quality, and personnel operation. Specific precautions are as follows:

1、 Preparation before startup: Ensure compatibility between equipment and raw materials

Raw material quality inspection and pretreatment

        Confirm that the specifications (thickness, width) and material (copper purity ≥ 99.9%) of the copper strip substrate meet the processing requirements of the rolling mill, and that the surface is free of oxidation, oil stains, scratches, and burrs to avoid impurities damaging the rolling mill or causing surface defects in the finished welded strip.

        If there is an oxide layer on the surface of the copper strip, acid washing and polishing treatment should be carried out first; If there is oil contamination, use a specialized cleaning agent to wipe it clean and air dry it to prevent slipping or poor adhesion of the coating during rolling.

        Check the uniformity of the solder strip coating (such as tin plating). If it is a pre tinned copper strip, it is necessary to confirm that the coating thickness meets the standard to avoid cracking and peeling of the coating after rolling.

Equipment parameter calibration and inspection

        Accurately adjust the rolling pressure, roll gap, and rolling speed of the rolling mill based on the thickness and width of the target welding strip (conventional photovoltaic welding strip thickness of 0.08-0.3mm). Before the first rolling, a trial rolling is required to ensure even roll gaps through multiple fine adjustments, avoiding situations where one side is thick or thin.

        Check the surface condition of the rolling mill: The rolling mill should be smooth, free of damage, copper adhesion, and rust. If there are scratches or wear, they should be polished or replaced in a timely manner, otherwise they will be directly copied to the surface of the welding strip, affecting the subsequent welding conductivity.

        Confirm that all components of the equipment are operating normally, including the transmission system, tension control system, guide device, and winding device. The tension should be stable and moderate (too tight can easily break the copper strip, and too loose can cause the strip to deviate), and the guide wheel should be aligned with the centerline of the copper strip.

        Check the lubrication system: Ensure that the lubricating oil for the roller bearings and transmission gears is sufficient  and the oil quality is clean. Poor lubrication can cause equipment noise, high roller temperature rise, and affect rolling accuracy.

Security protection inspection

        Confirm that the safety protection cover, emergency stop button, and protective fence of the equipment are intact and effective, the grounding device is reliable, and prevent the strip from breaking and flying out or parts from falling off during high-speed operation, which may cause injury.

        Check the workshop environment: keep the operating area clean and dry, free of dust and debris, control the temperature at 15-30 ℃, humidity ≤ 60%, and prevent copper strip oxidation or equipment electrical components from getting damp.

2、 Operation during rolling process: strict control of precision and quality

Real time monitoring of product quality

      Monitor the thickness accuracy of the welding strip throughout the process: Use a micrometer or online thickness gauge to conduct regular spot checks to ensure that the thickness deviation is controlled within ± 0.003mm (photovoltaic welding strips require extremely high thickness accuracy, and excessive deviation can affect the current conduction efficiency of the component).

      Observe the surface condition of the welded strip: The finished welded strip should have a smooth surface, no indentation, no wrinkles, no coating peeling, and no burrs or curled edges on the edges. If there are surface defects, the machine should be stopped immediately to inspect the rolling mill or raw materials.

      Control rolling speed: Adjust the speed according to the thickness of the copper strip. For thin specification welding strips (≤ 0.1mm), reduce the rolling speed to avoid stretching deformation or fracture of the strip; Strictly prohibit speeding rolling to prevent equipment overload.

Equipment operation status monitoring

       Pay attention to the sound of equipment operation: During normal rolling, the equipment should be stable without any abnormal noise. If there is a sound of metal impact or sharp friction, the machine should be stopped immediately for inspection to check for problems such as roller misalignment, bearing damage, and loose transmission components.

       Monitoring the temperature of the rolling mill: During the rolling process, the rolling mill will experience a temperature rise due to friction, and the temperature should be controlled to be ≤ 60 ℃. If the temperature rise is too fast, the cooling system (water cooling or air cooling) can be turned on to prevent the rolling mill from expanding and causing changes in the roll gap, which will affect the accuracy.

       Preventing strip deviation: Real time observation of the copper strip's travel trajectory. If deviation occurs, the guiding device or winding tension should be fine tuned to avoid friction damage between the strip edge and equipment components, or equipment jamming caused by rolling into the rolling mill.

Standardized operation of personnel

       Operators are required to wear personal protective equipment (gloves, protective goggles, work clothes) and are strictly prohibited from directly touching the rolling mill and strip during operation with their hands to prevent injury from entanglement.

       It is strictly prohibited to perform cleaning, adjustment, maintenance, and other operations while the equipment is in operation. If troubleshooting is required, the machine must be stopped, the power must be cut off, and a "Do Not Close" warning sign must be hung.

       When collaborating with multiple people, clear division of labor is required, and before starting up, it is necessary to confirm that all personnel are in a safe area to avoid misoperation.

3、 Maintenance and upkeep after shutdown: extending equipment lifespan

Equipment cleaning

       Clean the copper shavings and oil stains on the surface of the rolling mill in a timely manner after shutdown, and wipe the rolling mill with a soft cloth to avoid residual impurities that may cause indentation during the next rolling process; Clean up the waste on the winding device and keep the equipment clean.

       Clean the electrical control cabinet and heat dissipation vents to prevent dust accumulation from affecting the heat dissipation of electrical components and causing malfunctions.

Regular maintenance and upkeep

       Roll maintenance: Regularly inspect and polish the accuracy of the rolls, and replace them in a timely manner when they are severely worn; When the machine is shut down for a long time, it is necessary to apply anti rust oil on the surface of the rolling mill and wrap it with protective film to prevent rusting.

       Lubrication and maintenance: Regularly replace lubricating oil, clean lubrication pipelines, and ensure sufficient lubrication of all moving parts; Check the oil pressure and level of the hydraulic system, replenish the hydraulic oil in a timely manner, and filter impurities.

       Replacement of vulnerable parts: Regularly check the wear and tear of vulnerable parts such as transmission belts, guide wheels, and winding clamps. Replace them immediately when aging or deformation occurs to avoid affecting the stability of equipment operation.

       Electrical system maintenance: Regularly check whether the wiring of electrical components such as motors, sensors, and frequency converters is loose, whether the insulation is good, and ensure the electrical safety of the equipment.

Storage of finished products and raw materials

       The rolled welding strips should be classified and coiled according to specifications, wrapped with moisture-proof film, labeled with specifications and production date, and stored in a dry and ventilated warehouse to avoid oxidation and deformation.

       Unprocessed copper strip substrates should be stored elevated and kept away from acidic, alkaline, and humid environments to prevent corrosion.

4、 Abnormal situation handling: timely stop loss and risk prevention

       If the welding strip breaks, immediately stop the machine, cut off the power, clean the broken strip, investigate the cause (such as excessive tension, raw material defects, and small roller gap), adjust the parameters, and try rolling again.

       If the temperature of the rolling mill is found to be abnormally high, stop the machine and check if the cooling system is faulty or if the lubrication is insufficient. Wait until the temperature drops to normal before running again.

       If the equipment has serious faults such as leakage, abnormal noise, and severe vibration, immediately press the emergency stop button, cut off the main power supply, contact professional maintenance personnel for handling, and it is strictly prohibited to disassemble it by oneself.